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Purpose: Seizure originates from different pathological substrate; however, the same pathologies may have distinct mechanisms underlying seizure generation. We aimed to improve the understanding of such mechanisms in patients with temporal lobe epilepsy (TLE) by investigating the stereoelectroencephalography (SEEG) ictal onset patterns (IOPs). Methods: We analyzed data from a cohort of 19 consecutive patients explored by SEEG and had 1–3-year seizure-freedom following temporal lobe resection. Results: Six IOPs were identified. They were low voltage fast activity (LVFA) (36.5%), rhythmic spikes or spike-waves at low frequency and with high amplitude (34.1%), runs of spikes (10.6%), rhythmic sharp waves (8.2%), low frequency high amplitude repetitive spiking (LFRS) (7.1%), and delta activity (3.5%). All six patterns were found in patients with mesial temporal onset and only two patterns were found in patients with temporal neocortical onset. The most prevalent patterns for patients with mesial temporal onset were rhythmic spikes or spike-waves, followed by LVFA with a mean discharge rate 74 Hz. For patients with temporal neocortical onset, the most prevalent IOP pattern was LVFA with a mean discharge rate 35 Hz, followed by runs of spikes. Compared with Lateral TLE (LTLE), the duration between the onset of the IOPs to the onset of the symptom was longer for patients with MTLE (Mesial TLE) (MTLE:55.7 ± 50.6 s vs LTLE:19.5 ± 16.4 s). Conclusion: Multiple IOPs underlie seizure generation in patients with TLE. However, the mesial and lateral temporal lobes share distinct IOPs. [ABSTRACT FROM AUTHOR]

Summary Object To study the role of epilepsy surgery for patients with focal lesions who exhibited the semiology of clinically generalised seizures. Methods From our epilepsy surgery series, we identified 29 patients who underwent surgery for seizures, including certain types of generalised seizures, according to their ictal semiology. We systematically reviewed the brain imaging, video-EEG, surgical operation, and pathological findings data of these patients. Results All patients had at least one type of generalised seizure according to the semiology; these seizures included epileptic spasms, myoclonic seizures, tonic seizures, atonic seizures and atypical absence seizures. Eight patients had a single type of seizure, 11 patients had two types of seizures, and 10 patients had more than two types of seizures. In addition to symptomatic generalised seizures, complex partial seizures were also recorded in eight patients. In 24 patients, the ictal semiology showed slight asymmetric movements in certain types of seizures. Generalised interictal epileptic discharges were recorded in 24 patients; and generalised ictal epileptic discharges as the only EEG pattern were recorded in 13 patients. Intracranial recording was performed in 20 patients; 10 of whom showed a rhythm of fast activities at the initiation of the seizures. Functional hemispherectomy was performed for three patients with hemispheric lesions. Focal resection of the epileptogenic zone was performed in 26 patients. The resected epileptogenic zones involved a single lobe in 10 patients, two lobes in 11 patients, and three lobes in 5 patients; the parietal lobe was the most commonly involved lobe (in 19 cases). Scar lesions (in 17 patients) were most commonly observed on pathological examination. At the last follow-up (mean 18 ± 8.3 months, range 12–48), 17 (58.6%) patients were seizure-free. Conclusions Certain patients with local brain lesions can have seizures with specific types of generalised semiology. An appropriate operation may be helpful for a portion of these patients. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The goal of this study was to summarize the results of language cortex mapping using electrical cortical stimulation with modified language tasks for Mandarin-speaking patients with epilepsy. Methods: Electrical currents were delivered through implanted subdural electrodes to six Mandarin-speaking patients before epilepsy surgery. The current intensities inducing any language disturbance during comprehension, repetition, and speech tasks were recorded, and individual cortical mapping was completed to guide subsequent resection, with the distance between mapped language sites and resected zones kept at a minimum of 0.5cm. Language function was reassessed and followed up after surgery. Results: Language cortices were successfully identified in three patients, but demonstrated great variability in distribution. There seemed to be no difference in the intensity threshold that induced language interference. None of the six patients exhibited language deficits postsurgery. Conclusions: Electrical cortical stimulation with modified language tasks is valid for identification of cortices underlying Mandarin processing. The great variability in language cortex distribution enhances the necessity of individual language cortical mapping in epilepsy surgery. [ABSTRACT FROM AUTHOR]

The objective of the study was to develop and clinically test a trial-free online-based language mapping method for localizing the eloquent cortex easily in epilepsy operation. Nine patients with refractory epilepsy were included in this study according to the results of preoperative evaluation for their epileptogenic zones (EZs) located adjacent to the eloquent cortex. When patients were awakened up from general anesthesia during operation, the trial-free online-based language-mapping paradigm was performed. All positive points marked on the cortex in each test were labeled and superimposed together as the result of functional mapping for each patient. The eloquent cortex was mapped according to the results obtained both from the intraoperative trial-free task localization method and the traditional electrical cortical stimulation (ECS). All patients completed this paradigms twice within 10 min. Based on the results of mapping, the EZs were tried to fully resected on the premise of preserving the mapped eloquent cortex as much as possible. The postoperative follow-up showed the outcome of Engel I in six patients and Engel II in three patients, whereas only two patients had aphemia after surgery and recovered within one week and three months, respectively. The intraoperative trial-free online-based language mapping method was primarily identified to be safe and effective. This novel method seems to be promising and worthy of improvement. • A trial-free online-based language mapping paradigms is newly developed. • Language mapping by HGP is low-risk, timesaving, and multiprocessing. • The novel language mapping paradigms were underwent easily and quickly in operation. • This language mapping method is primarily verified safe and effective. [ABSTRACT FROM AUTHOR]